1. Field of the Invention
The present invention relates to an entry detection apparatus and method for detecting entry of a vehicle into an entry prohibited road.
2. Description of Related Art
Japanese Patent Application Laid-open No. 2007-293390 describes a warning device which detects whether an own vehicle is running in the wrong direction based on a road sign in an image ahead of the own vehicle captured by an image sensor, and gives a warning to the vehicle driver if the own vehicle is detected to be running in the wrong direction.
Also, there is known a car navigation device configured to associate information showing entry prohibition with link information showing a road section. According to this car navigation device, it is possible to identify the road section in which the own vehicle is running using information showing the position of the own vehicle, and determine whether or not the own vehicle is running on an entry prohibited road using the link information.
However, since installation places of road signs vary from country to country, the warning device described in the above patent document cannot completely correctly determine whether the own vehicle is running in the wrong direction. Accordingly, there may be a case where the warning device issues a warning although the own vehicle is not running in the wrong direction.
On the other hand, in a case where the position of the own vehicle is detected using a car navigation device, since the GPS positioning error may be as large as several meters, an error may occur in determining whether or not the own vehicle is entering an entry prohibited road, for example, when the entry prohibited road is adjacent to an expressway ramp.